While the telephone system as a means of communication has grown from an instrument of convenience to one of necessity, there are still occasions when telephone calls may offer some inconvenience to the customers using the system.
For example, most calls are originated at the complete discretion of the calling customer who not only chooses the called customer but selects the time and place from which the call originates.
Although the call is placed at the convenience of the call originator, the called customer may not wish to be disturbed at this time and, indeed, may be at some other location.
Arrangements are available for blocking calls or routing calls to an answering service so as not to disturb the called customer. Furthermore, there are arrangements for forwarding incoming calls to another location where the called party can be reached or where an associate at that location can accept the call.
While these arrangements are wholly suitable for their intended purpose, they generally treat all incoming calls in the same manner. Thus, if the called customer elects not to be disturbed, all calls will be blocked unless they are routed via an attendant or secretary who can exercise discretion by allowing only selected important calls to reach the called customer.
Insofar as billing in a telephone system is concerned, most calls are billed to the calling customer. Although some calls can be billed to the called customer or to a third party, these calls require the service of an attendant to ascertain whether the party to be billed will accept the charges. Of course, the call may be delayed while the attendant verifies if the charges will be accepted.
Accordingly, with the above described and other special services there is no selective processing of calls under the control of the called customer without the intervention of an attendant.